Bear with me this is 2nd hand knowledge. My girlfriend has an 88 ranger 2.9v6 she uses as a farm truck. She says that every now and then the engine sputters and dies and she can smell un-burned gas coming out of the tailpipe. She also says that when it idles it somtime revs up and down. I told her I would take a look at it tomorrow. I'm thinking its the TPS. Any Ideas?